CN101874371A

CN101874371A - Signal demodulation device, signal demodulation method, semiconductor integrated circuit, and reception device

Info

Publication number: CN101874371A
Application number: CN200880117599A
Authority: CN
Inventors: 八木铁也; 林贵也; 林健一郎; 木村知弘
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 2007-11-27
Filing date: 2008-10-28
Publication date: 2010-10-27
Also published as: US20100275102A1; EP2197134A1; JPWO2009069420A1; WO2009069420A1

Abstract

A time frequency conversion unit (6) which converts a frequency division multiplex signal on a time axis into a signal on a frequency axis and outputs a data carrier, a pilot carrier, and a transmission control carrier, an equalization unit (7) which equalizes the data carrier and the transmission control carrier according to a transmission path characteristic value obtained from the pilot carrier and outputs the equalized data carrier and the equalized transmission control carrier, a first decoding unit (9) which decodes the equalized transmission control carrier, and a first correction unit (10) which performs an error correction of the output of the first decoding unit (9) and outputs first control information and a first decode flag indicating the state of the error correction are included.

Description

Signal demodulating equipment, signal demodulating method, semiconductor integrated circuit and receiving system

Technical field

Signal demodulating equipment, signal demodulating method, semiconductor integrated circuit and receiving system that the orthogonal frequency-division multiplex singal that the present invention relates to frequency-division multiplex singal, especially terrestrial digital broadcasting are adopted (below, be called " ofdm signal ") carries out demodulation.

Background technology

China since 2003 according to the ISDB-T specification terrestrial digital broadcasting.In addition, from Europe, North America, South America, Asia circle, thereby just beginning terrestrial digital broadcasting is carried out in the analog broadcasting digitlization in countries in the world.Wherein a plurality of country adopts equal or follow its technology with the ISDB-T mode of Japan, has especially adopted the ofdm signal at the most carrier waves of frequency axis orthogonal multiplex.

Ofdm signal contains the transmission of Information control carrier wave passing on modulation system and send frequency band etc., be used to the data carrier of calculating the pilot frequency carrier wave of transmission path characteristic and containing real data.In addition, ofdm signal multiplexing these carrier waves on frequency axis.Therefore, signal demodulating equipment adopts with high speed Fourier (Fourier) conversion (below, be called " FFT ") and for the temporal frequency conversion of representative, the carrier wave that is re-used is carried out demodulation, and detects frame synchronization.

This signal demodulating equipment is decoded to the transmission control carrier wave that is obtained by the temporal frequency conversion, thereby obtains the information (for example with reference to patent documentation 1 (spy opens the 2002-247003 communique)) of modulation system and transmission frequency band etc.Here, in the signal demodulating equipment in the prior art, the transmission control carrier wave that comprises in the output of temporal frequency converter section is decoded.

Figure 18 is the module map of signal demodulating equipment of the prior art.

Signal demodulating equipment 100 possesses antenna 101, tuner 102, analog digital converter section 103, detection section 104, temporal frequency converter section 105, balanced portion 106, error correction portion 107, lsb decoder 108, corrects portion 109 and synchronous detecting portion 110.

The received signal that comprises ofdm signal is the signal on the time shaft, be received by antenna 101, the signal that has passed through the time shaft of tuner 102, analog digital converter section 103, detection section 104 is converted into the signal on the frequency axis in temporal frequency converter section 105.Take out the transmission that on frequency axis, is re-used thus and control carrier wave etc.

108 pairs of transmission control carrier waves from 105 outputs of temporal frequency converter section of lsb decoder are decoded.Correct the mistake that portion 109 corrects decoded transmission control carrier wave.Frame synchronization detects in synchronous detecting portion 110.Transmission after error correction control carrier wave and frame synchronization are exported to the outer key element of figure as each control information and synchronizing information, and are utilized in the signal demodulation.

So, existing signal demodulating equipment will be used for the decoding of control information and synchronizing information at the transmission control carrier wave that temporal frequency converter section 105 extracts.

Patent documentation 1: the spy opens the 2002-247003 communique

The decoding processing of the transmission control carrier wave that existing signal demodulating equipment is included has the strong feature of anti-white noise (white noise).

Here, adopt the terrestrial digital broadcasting of ofdm signal not only to be used for fixedly receiving system of arrangement type, also be used for mobile receiving systems such as in-car TV and portable phone.In move receiving, common white noise is not only arranged, also by situation based on the noise grow of multipath or decay etc.

In addition, the ofdm signal in the ISDB-T specification is 13 sections with a band segmentation, comprises 13 sections 1 section broadcasting broadcasting and only use the carrier wave of a section of the carrier wave that uses whole 13 sections.In mobile the reception, adopt this 1 section broadcasting more, because carrier number is few, the decoding of the carrier wave of transmission control in the prior art becomes difficult mostly.Equally, the detection of frame synchronization also becomes difficulty in the prior art easily.

And, even say so mobile receiving system, also be existing situation about moving, situation about not moving is arranged again.That is, be that white noise plays the reception environment of mastery effect or the reception environment that attenuate acoustic noise plays the mastery effect, change constantly according to situation.Therefore, in the prior art, in move receiving, the become problem of difficulty of the decoding of the transmission control carrier wave of the changed condition followed is arranged.

Summary of the invention

Therefore, the object of the invention is to provide signal demodulating equipment, signal demodulating method, semiconductor integrated circuit and the receiving system of the detection of a kind of, the decoding that can transmit control carrier wave corresponding with variation reception environment and frame synchronization.

In order to solve above problem, signal demodulating equipment of the present invention possesses: the temporal frequency converter section, and it is converted to signal on the frequency axis with the frequency-division multiplex singal on the time shaft, dateout carrier wave, pilot frequency carrier wave and transmission control carrier wave; Equilibrium portion, it carries out equilibrium according to from the transmission path characteristic value that pilot frequency carrier wave obtained to data carrier and transmission control carrier wave, output equalization data carrier wave and balanced transmission control carrier wave; The 1st lsb decoder, it is decoded to equilibrium transmission control carrier wave; With the 1st correct portion, error correction is carried out in its output to the 1st lsb decoder, export the 1st control information and expression error correction state the 1st separate code labeling (flag).

The invention effect

The present invention is the suitableeest and at high speed corresponding to the noise circumstance that at every moment changes, and decoding and the frame synchronization that can transmit the control carrier wave detect.Especially, demodulating equipment can be corresponding to the white noise environment and the attenuate acoustic noise environment that change easily in mobile environment.

In addition, the present invention can also be the suitablelyyest corresponding to 1 section broadcasting a little less than the variation of antinoise environment.

Detect antinoise by transmission control carrier wave decoding and frame synchronization and change grow, thereby also improve the demodulation accuracy of ofdm signal.

Description of drawings

Fig. 1 is the schematic diagram of the ofdm signal in the embodiments of the present invention 1.

Fig. 2 is the key diagram of the Carrier State of the ofdm signal in the expression embodiments of the present invention 1.

Fig. 3 is the key diagram of the section structure of the ofdm signal in the expression embodiments of the present invention 1.

Fig. 4 is the module map of the signal demodulating equipment in the embodiments of the present invention 1.

Fig. 5 is the internal module figure of the 1st lsb decoder in the embodiments of the present invention 1.

Fig. 6 is that the 1st in the embodiments of the present invention 1 are corrected the internal module figure that portion and the 2nd corrects portion.

Fig. 7 is the result of emulation is carried out in expression to the decode precision of in the present invention the 1st lsb decoder and the 2nd lsb decoder a curve chart.

Fig. 8 is the 1st synchronous detecting portion in the embodiments of the present invention 1 and the internal module figure of the 2nd synchronous detecting portion.

Fig. 9 is the result of emulation is carried out in expression to the decode precision of in the present invention the 1st lsb decoder and the 2nd lsb decoder a curve chart.

Figure 10 is the internal module figure of the balanced portion in the embodiments of the present invention 2.

Figure 11 is the internal module figure of the 2nd lsb decoder in the embodiments of the present invention 2.

Figure 12 is the key diagram that the mark in the embodiments of the present invention 3 is selected.

Figure 13 is the module map that realizes the device of the signal demodulating method in the embodiments of the present invention 4.

Figure 14 is the flow chart of the signal demodulating method in the embodiments of the present invention 4.

Figure 15 is the module map of the semiconductor integrated circuit in the embodiments of the present invention 5.

Figure 16 is the module map of the receiving system in the embodiments of the present invention 6.

Figure 17 is the stereogram of the portable phone in the embodiments of the present invention 6.

Figure 18 is the module map of existing signal demodulating equipment.

Symbol description

1 signal demodulating equipment

2 antennas

3 tuners

4 analog digital converter sections

5 detection sections

6 temporal frequency converter sections

7 balanced portions

8 error correction portions

9 the 1st lsb decoders

10 the 1st correct portion

11 the 1st synchronous detecting portions

12 control information conciliation portions

13 synchronizing information conciliation portions

14 the 2nd lsb decoders

15 the 2nd correct portion

16 the 2nd synchronous detecting portions

Embodiment

The signal demodulating equipment of the 1st invention possesses: the temporal frequency converter section, and it is converted to signal on the frequency axis with the frequency-division multiplex singal on the time shaft, dateout carrier wave, pilot frequency carrier wave and transmission control carrier wave; Equilibrium portion, it carries out equilibrium according to from the transmission path characteristic value that pilot frequency carrier wave obtained to data carrier and transmission control carrier wave, output equalization data carrier wave and balanced transmission control carrier wave; The 1st lsb decoder, it is decoded to equilibrium transmission control carrier wave; With the 1st correct portion, error correction is carried out in its output to the 1st lsb decoder, export the 1st control information and expression error correction state the 1st separate code labeling.

According to this structure, signal demodulating equipment can have abundant resistance ground decoding transmission control carrier wave at attenuate acoustic noise.Even the attenuate acoustic noise grow that is caused by the variation of reception environment especially, signal demodulating equipment also can be with sufficient precision decoding transmission control carrier wave.

In the signal demodulating equipment of the 2nd invention, on the basis of the 1st invention, also possess: the 2nd lsb decoder, it is decoded to the transmission control carrier wave from the output of temporal frequency converter section; The 2nd corrects portion, and error correction is carried out in its output to the 2nd lsb decoder, thus export the 2nd control information and expression error correction state the 2nd separate code labeling; With control information conciliation portion, it separates code labeling and the 2nd at least one of separating in the code labeling according to the 1st, selects in the 1st control information and the 2nd control information any.

According to this structure, signal demodulating equipment can use the 1st control information that attenuate acoustic noise is had strong resistance in the attenuate acoustic noise environment, can use the 2nd control information that white noise environment is had strong resistance in white noise environment.As a result, the precision of signal demodulation improves.

In the signal demodulating equipment of the 3rd invention, on the basis of the 2nd invention, also possess: the 1st synchronous detecting portion, its output according to the 1st lsb decoder detects frame synchronization, exports the 1st sync mark of the state of the 1st synchronizing information and the detection of expression frame synchronization; The 2nd synchronous detecting portion, its output according to the 2nd lsb decoder detects frame synchronization, exports the 2nd sync mark of the state of the 2nd synchronizing information and the detection of expression frame synchronization; With synchronizing information conciliation portion, it selects any in the 1st synchronizing information and the 2nd synchronizing information according in the 1st sync mark and the 2nd sync mark at least one.

According to this structure, signal demodulating equipment can use the 1st strong synchronizing information of antidamping noise in the attenuate acoustic noise environment, can use the 2nd strong synchronizing information of anti-white noise environment in white noise environment.As a result, the precision of signal demodulation improves.

In the signal demodulating equipment of the 4th invention, on the basis of the 3rd invention, the 1st separates code labeling comprises that expression correctly carried out the situation of " intact " of error correction situation " finishing " of the 1st control information and the situation that error correction is not correctly carried out in expression, the 2nd separates code labeling comprises that expression correctly carried out the situation of " intact " of error correction situation " finishing " of the 2nd control information and the situation that error correction is not correctly carried out in expression, the 1st sync mark and the 2nd sync mark comprise respectively expression can detect frame synchronization situation " detecting " and represent to detect the situation of " not detecting " of the situation of frame synchronization.

According to this structure, signal demodulating equipment can be selected high control information of decode precision and the high synchronizing information of accuracy of detection as required.As a result, the precision of signal demodulation improves.

In the signal demodulating equipment of the 5th invention, on the basis of the 4th invention, control information conciliation portion is selected in the 1st control information and the 2nd control information and the situation control information corresponding of finishing, and the synchronizing information corresponding with detected situation selected by synchronizing information conciliation portion in the 1st synchronizing information and the 2nd synchronizing information.

In the signal demodulating equipment of the 6th invention, on the basis of the 4th invention, control information conciliation portion separates code labeling and the 2nd decoding mark is represented under the situation of situation of same levels the 1st, the control information that selection has just been selected in the 1st control information and the 2nd control information, synchronizing information conciliation portion represents in the 1st sync mark and the 2nd sync mark to select the synchronizing information of just having selected under the situation of situation of same levels in the 1st synchronizing information and the 2nd synchronizing information.

According to this structure, signal demodulating equipment can be selected only control information and synchronizing information according to the variation of accepting state.

In the signal demodulating equipment of the 7th invention, on the basis of the 4th invention, control information conciliation portion of control information conciliation portion is in specified time limit, separating code labeling and the 2nd the 1st separates in the code labeling, the number of the situation that the metering expression is finished, control information conciliation portion is in the 1st control information and the 2nd control information, selection with Duo than number separate the code labeling control information corresponding, synchronizing information conciliation portion is in specified time limit, in the 1st sync mark and the 2nd sync mark, the number of the detected situation of metering expression, the synchronizing information corresponding with the sync mark of Duoing than number selected by synchronizing information conciliation portion in the 1st synchronizing information and the 2nd synchronizing information.

Below, with reference to the description of drawings embodiments of the present invention.

In addition, in the following embodiments, be that the center describes with the ofdm signal of following the ISDB-T specification, even but the frequency-division multiplex singal that on frequency axis, is re-used based on the ofdm signal beyond the ISDB-T specification or carrier wave etc., too, the present invention also comprises these signal decoding.

The control information (the 1st control information, the 2nd control information) of record comprises that TMCC signal in the ISDB-T specification is as its 1 example in this manual in addition.

In addition, " the 1st " in this specification, " the 2nd " such term use in order to distinguish same key element certainly, do not increase qualification especially, also do not get rid of the situation of further appending same key element.

(execution mode 1)

At first, adopt Fig. 1, Fig. 2, Fig. 3 explanation to follow the ofdm signal of ISDB-T specification.

Fig. 1 is the schematic diagram of the ofdm signal in the embodiments of the present invention 1.Ofdm signal is multiplexing a plurality of carrier waves on frequency axis.Be re-used thereby especially carrier wave is orthogonal.It is generally acknowledged that such ofdm signal anti-multipath is strong.

Fig. 2 is the key diagram of the Carrier State of the ofdm signal in the expression embodiments of the present invention 1.As shown in Figure 2, thus ofdm signal forms a signal code (below, be called " symbol "), multiplexing this symbol on time shaft at multiplexing a plurality of carrier waves on the frequency axis.

The carrier wave that ofdm signal contains the data that comprise that image or sound are modulated is data carrier, be used to calculate the pilot frequency carrier wave and the transmission transmission of Information control carrier wave relevant with the transmission of modulation system or frequency band etc. of transmission path state.

As shown in Figure 2, transmission control carrier wave is present in the same position of each symbol.Pilot frequency carrier wave disposes at certain intervals.Data carrier is configured in the position that does not have transmission control carrier wave and pilot frequency carrier wave.

As shown in Figure 3, in the ISDB-T specification, 1 ofdm signal frequency band is split into 13 sections.Use the broadcasting of whole these 13 sections to be called 13 sections broadcasting, only used 1 section broadcasting of central authorities to be called 1 section broadcasting.1 section broadcasting multiaspect is utilized to mobile body terminal such as portable terminal device or car-mounted terminal.

As shown in Figure 3, in 1 section broadcasting, compare with 13 sections broadcasting, the quantity of employed carrier wave is few, the difficulty so the decoding of transmission control carrier wave or data carrier becomes easily.

Below, the structure that adopts Fig. 4, Fig. 5 explanation that the equilibrium transmission control carrier wave that has carried out equilibrium treatment is decoded.

7 pairs of data carrier and transmission control carrier waves from temporal frequency converter section 6 outputs described later of equilibrium portion carry out equilibrium.Equilibrium portion 7 usefulness known pilot carrier waves carry out multiple division to the pilot frequency carrier wave from 6 outputs of temporal frequency converter section, calculate the displacement of its amplitude and phase place.Equilibrium portion 7 adopts this displacement of calculating that thereby data carrier and transmission control carrier wave are carried out multiple division equilibrium.Equalization data carrier wave after 7 these equilibriums of output of equilibrium portion and balanced transmission control carrier wave.

Equalization data carrier wave after the equilibrium and balanced transmission control carrier wave are the signals of having considered the transmission path state, so the signal condition when sending is considered to carry out correct decoding.

Signal demodulating equipment in the execution mode 1 adopts this equilibrium transmission control carrier wave to decode.For this decoding, possess the 1st lsb decoder the 9, the 1st and correct portion 10 and the 1st synchronous detecting portion 11.

The details of each one below is described.

(the 1st lsb decoder)

The 1st lsb decoder 9 is by differential decoding, and carrier wave is controlled in the balanced transmission of decoding.

The 1st lsb decoder 9 possesses complex division portion 20, accumulation addition portion 21, polarity judging portion 22, differential lsb decoder 23 and differential benchmark portion 24.

Differential benchmark generating unit 24 produces the fiducial value in the differential decoding and exports to complex division portion 20.Complex division portion this fiducial value of 20 usefulness is carried out multiple division to equilibrium transmission control carrier wave.Accumulation addition portion 21 is a plurality of balanced transmission control carrier waves behind the multiple division of addition cumulatively.Polarity judging portion 22 judges that balanced transmission control carrier wave is present in positive zone and still is present in negative zone on orthogonal plane.Differential lsb decoder 23 carries out the decoding of balanced transmission control carrier wave according to these judgements, and the output result.The result of this output is the 1st control information.

In addition, the 1st control information of balanced transmission control carrier waves outputs " before the error correction " thereby the 1st lsb decoder 9 is decoded, the 1st corrects 10 pairs of the 1st control informations of being somebody's turn to do " before the error correction " of portion carries out error correction, the 1st control information of output " after the error correction ".

In this manual, for control information (comprise the 1st control information and the 2nd control information any) record, under the situation that does not need additional symbols, record " before the error correction " and " after the error correction " especially.

In addition, the 1st lsb decoder 9 except structure shown in Figure 5 can also be and the identical structure (shown in Figure 11) of the 2nd lsb decoder 14 described later.

(the 1st corrects portion)

The 1st of Fig. 4 corrects the error correction that portion 10 carries out controlling in the 9 decoded transmission of the 1st lsb decoder carrier waves, exports the 1st control information.The 1st control information comprises the needed information of demodulation of ofdm signals such as the modulation system that contained in the transmission control carrier wave, frequency band.

The 1st corrects portion 10 has with the described later the 2nd and corrects the identical structure of portion 15.

The 1st corrects portion 10 possesses (syndrome) register 50 of makeing mistakes, wrong detection unit 51, make mistakes and operational part 52, majority determine detection unit 53 and data register 54.

As shown in Figure 6, adopt Fig. 6 to illustrate that the 1st corrects the action of portion 10.Fig. 6 is that the 1st in the embodiments of the present invention 1 are corrected the internal module figure that portion and the 2nd corrects portion.Here, carry out the explanation of correcting portion 10 to the 1st, but the described later the 2nd corrects portion 15 too.

At first, empty the register 50 of makeing mistakes.Then, once be shifted 1 ground input make mistakes register 50 and data register 54 of the 1st control information position (comprising check digit) that becomes the error correction object.And, 89 branches of register 50 cyclic shifts of makeing mistakes (, using 89 abbreviated codes " 184,102 " of difference set cyclic code " 273,191 ") because as the ISDB-T specification.

Then, error detection (make mistakes and computing and most decision are judged) is carried out to everybody in register 50 and data register 54 limits 1 limit of each displacement of makeing mistakes.When arbitrary position detects mistake, error correction (based on the bit reversal of XOR) is carried out in the output of the output of data register 54 and the register 50 of makeing mistakes.This moment the data register 54 corrected output as error correction after the 1st control information position export successively.

At last, after whole the error detection of being stored in the data register 54/correct processing finished, check the position of the register 50 of makeing mistakes.If carried out correct correcting, whole value of the register 50 of then makeing mistakes should become value " 0 ".If not, then regard as wrong, the output error certification mark.So, correct portion 10 by error correction the 1st, export as the 1st control information at the 1st transmission control carrier wave of the 1st lsb decoder 9 decodings.At this moment, correcting to regard as in the portion 10 the 1st does not have under the wrong situation, and the 1st situation of correcting portion's 10 outputs " finishing " is separated code labeling as the 1st, regarding as under the vicious situation, output comprise " intact " situation the 1st separate code labeling.

As described above, thus the signal demodulating equipment in the embodiments of the present invention 1 uses by the transmission of the equilibrium after 7 equilibriums of balanced portion control carrier wave transmission control carrier wave to be decoded and obtains the 1st control information.

In balanced portion 7, carried out the revisal corresponding with the transmission path state by the transmission of the equilibrium after equilibrium control carrier wave.The equilibrium that equilibrium portion 7 carries out is the revisal to multipath or attenuate acoustic noise, and balanced transmission control carrier wave has strong resistance to attenuate acoustic noise.

The 1st lsb decoder 9 and the 1st is corrected the strong equilibrium transmission control carrier wave of the such antidamping noise of portion's 10 decodings, so the 2nd control information of being exported is to the reliability and the correctness height of attenuate acoustic noise.

The situation of the resistance of 9 pairs of attenuate acoustic noise of the 1st lsb decoder of the balanced transmission control of employing carrier wave is shown in Figure 7.

Here, 14 pairs of transmission control carrier waves by before balanced as the output of temporal frequency converter section 6 of the 2nd lsb decoder are decoded the details aftermentioned.

In the curve chart of Fig. 7, the longitudinal axis is represented the error rate (below, be called " BER "), and transverse axis is represented Doppler (Doppler) frequency of analog attenuation noise circumstance.As shown in Figure 7, the decode precision of the 1st lsb decoder 9 is better than the decode precision of the 2nd lsb decoder 14.Especially, surpass decoding boundary (dotted line in the curve chart) when Doppler frequency surpasses 120Hz in the 2nd lsb decoder 14, become in the reality and can not transmit the decoding of control carrier wave.

So, by using the equilibrium transmission control carrier wave after the equilibrium, thereby the 1st lsb decoder 9 (and the 1st correct portion 10) can have strong resistance ground decoding transmission control carrier wave to the attenuate acoustic noise environment.

(the 1st synchronous detecting portion)

Synchronizing signal detects from the output of the 1st lsb decoder 9 in the 1st synchronous detecting portion 11 of Fig. 4, detects frame synchronization.Fig. 8 is the 1st synchronous detecting portion in the embodiments of the present invention 1 and the internal module figure of the 2nd synchronous detecting portion.Here, the 1st synchronous detecting portion 11 is described, but the 2nd synchronous detecting portion 16 described later too.Here, so-called frame is unit a kind of of ofdm signal, is based on the unit of the symbol of specified quantity.

The 1st synchronous detecting portion 11 possesses synchronization signal detection portion 60, synchronous protection portion 61.60 pairs of the 1st control informations from 9 outputs of the 1st lsb decoder of synchronization signal detection portion detect has " synchronizing signal " of definite bit pattern.

Whether synchronous protection portion 61 has detected synchronizing signal by every frame inspection, under the situation that has detected synchronizing signal, and the 1st synchronizing information of the beginning position of output expression frame.And the 61 output expressions of synchronous protection portion have detected the 1st sync mark of synchronizing signal.The 1st sync mark comprises " detecting " situation and " not detecting " situation, and " detecting " situation represents to have detected synchronizing signal (having detected frame synchronization), and " not detecting " situation represents not detect synchronizing signal (not detecting frame synchronization).

At this moment, the 1st synchronous detecting portion 11 and the 1st lsb decoder 9 are same, carry out based in balanced portion 7 by the detection of the frame synchronization of the transmission control of the equilibrium after equilibrium carrier wave, so the antidamping noise is strong.

Signal demodulating equipment in the execution mode 1 possesses the 1st synchronous detecting portion 11 as required, can have strong resistance ground to the attenuate acoustic noise environment thus and detect frame synchronization.

(execution mode 2)

The following describes execution mode 2.In execution mode 2, adopt Fig. 4 to describe.

Signal demodulating equipment in the execution mode 2 also possesses: the 2nd synchronous detecting portion 16 that the 2nd lsb decoder the 14, the 2nd of decoding as the transmission control carrier wave of the output (before being the processing of balanced portion 7) of temporal frequency converter section 6 is corrected portion 15 and carried out the detection of frame synchronization.

Transmission control carrier wave in balanced portion 7 after the equilibrium has the characteristic to the resistance of attenuate acoustic noise, but because of the multiple division that has carried out based on estimated transmission path characteristic, (so-called Additive White Gaussian Noise is hereinafter referred to as " AWGN " to common white noise so also have.Also identical among the figure) characteristic that dies down.

To this, in having used the temporal frequency converter section 6 of FFT etc., extracted balanced before transmission control carrier wave have the antidamping noise a little less than but the characteristic of anti-white noise grow.

The environment that the electronic equipment (portable phone, portable terminal device, in-car TV, car-mounted terminal etc.) of signal demodulating equipment has been installed in encirclement can be followed and move and stop to change randomly.Therefore, reception environment has becomes white noise environment under certain situation, become the situation of attenuate acoustic noise environment in other cases.

Use is corrected portion 10 and the 1st synchronous detecting portion 11 antidamping noises are strong at the 1st lsb decoder the 9, the 1st of the equilibrium transmission control carrier wave of execution mode 1 explanation.The 2nd lsb decoder the 14, the 2nd is corrected the portion 15 and the 2nd synchronous detecting portion 16 anti-white noise sound intensitys.

Therefore, the signal demodulating equipment in the execution mode 2 can be according to the variation of noise circumstance, and the decoding and the frame synchronization of the transmission control carrier wave of applying in a flexible way detect.

At first, adopt Fig. 4 that the whole summary of signal demodulating equipment is described.

Signal demodulating equipment 1 in the execution mode 2 possesses antenna 2, tuner 3, analog digital converter section 4, detection section 5, temporal frequency converter section 6, balanced portion 7, error correction portion the 8, the 1st lsb decoder the 9, the 1st and corrects the 10, the 1st synchronous detecting portion 11 of portion, control information conciliation portion 12, synchronizing information conciliation portion the 13, the 2nd lsb decoder the 14, the 2nd and correct the 15, the 2nd synchronous detecting portion 16 of portion.In addition, also can delete the part of these key elements as required.

(overall description)

At first, whole summary is described.

Antenna 2 receives the transmitting signal that comprises ofdm signal.Tuner 3 receives the signal that comprises in definite frequency band of the received signal that is received, and exports to analog digital converter section 4.

Analog digital converter section 4 will be to export to detection section 5 after the digital signal from the analog signal conversion of tuner 3 output.5 pairs of digital signals of being imported of detection section are carried out detection, and the signal after the detection is exported to temporal frequency converter section 6.Temporal frequency converter section 6 is the signal of frequency axis from the conversion of signals of time shaft, mentions the data carrier, transmission control carrier wave and the pilot frequency carrier wave that are re-used on frequency axis.Equilibrium portion 7 is according to pilot frequency carrier wave transmission path estimation characteristic, and according to estimated transmission path characteristic, carrier wave is controlled in equalization data carrier wave and transmission.

Error correction portion 8 corrects by the mistake of the equalization data carrier wave after the equilibrium.This error correction data carrier comprise the information of image or sound, finally be used for the demodulation that image or sound show.So, signal demodulating equipment 1 carries out demodulation from the data that the ofdm signal taking-up that is received needs.

Arranged side by side with the demodulation of this data carrier, comprise that by the 1st lsb decoder 9～the 2nd synchronous detecting portion 16 becoming the required various transmission of Information of demodulation controls the decoding of carrier waves and the detection of frame synchronization.

Correct in the portion 10 at the 1st lsb decoder 9 and the 1st, the 1st strong control information of output antidamping noise is corrected in the portion 15 at the 2nd lsb decoder 14 and the 2nd, exports the 2nd control information of the anti-white noise sound intensity.The 2nd correct portion 15 output expression error correction state the 2nd separate code labeling.

Here, by simulation result shows based on the output of the temporal frequency converter section 6 before balanced promptly transmit the control carrier wave in the decoding of the 2nd lsb decoder 14 situation to the resistance of white noise.

Curve chart shown in Figure 9, the longitudinal axis is represented BER, transverse axis is represented the noisiness (AWGN is the abbreviation of expression white noise state) of simulating the white noise environment.As shown in Figure 9, the decode precision of the 2nd lsb decoder 14 is better than the decode precision of the 1st lsb decoder 9.

So, the 2nd lsb decoder 14 by having used the transmission control carrier wave before balanced (and the 2nd correct portion 15) can carry out the strong transmission control carrier wave decoding of anti-white noise environment.

That is, the 1st lsb decoder 9 can carry out the decoding of the strong transmission control carrier wave of antidamping noise circumstance and the detection of frame synchronization, and the 2nd lsb decoder 14 can carry out the decoding of the strong transmission control carrier wave of anti-white noise environment and the detection of frame synchronization, is can complementary structure.

Control information conciliation portion 12 separates at least one that code labeling and the 2nd is separated code labeling according to the 1st, select the 1st control information and the 2nd control information one.At this moment, select the high side of decode precision, so carry out the utilization with the variation control information corresponding of noise circumstance.

Equally, the 1st synchronizing information that the 1st synchronous detecting portion 11 output antidamping noises are strong and the 1st sync mark of expression frame synchronization detected state.The 2nd synchronizing information of the anti-white noise sound intensity of the 2nd synchronous detecting portion 16 outputs and the 2nd synchronizing information of expression frame synchronization detected state.

A side of the 1st synchronizing information and the 2nd synchronizing information selects according at least one of the 1st sync mark and the 2nd sync mark in synchronizing information conciliation portion 13.At this moment, the side that accuracy of detection is high is selected, so carry out the utilization of the synchronizing information corresponding with the variation of noise circumstance.

As described above, the signal demodulating equipment in the execution mode 21 carries out and the variation control information corresponding of noise circumstance and the utilization of synchronizing information.As a result, can realize the demodulation of the ofdm signal of suitable mobile reception.

The following describes the details of each one.

(antenna)

Antenna 2 receives the transmitting signal that comprises ofdm signal.

Antenna 2 can possess in the electronic equipment that signal demodulating equipment 1 has been installed, and under the situation of cab signal demodulating equipment 1, also can be installed in the automobile.

In addition, under the situation of carrying out diversity reception, a plurality of antennas can be installed.

(tuner)

Tuner 3 is according to the centre frequency corresponding with broadcast band, and selective reception is by definite frequency band of the ofdm signal of antenna 2 receptions.

Tuner 3 is exported to analog digital converter section 4 with the ofdm signal that is received as received signal.

In addition, under the frequency situation devious that frequency that tuner 3 uses and detection section 5 use, can carry out the revisal of frequency offset.

(analog digital converter section)

Analog digital converter section 4 analog signal conversion of self-tuner 3 in the future is a digital signal.Analog digital converter section 4 has and the corresponding resolution of the specification of signal demodulating equipment 1.

Digital signal after analog digital converter section 4 will be changed is exported to detection section 5.

(detection section)

5 pairs of digital signals from 4 outputs of analog digital converter section of detection section are carried out detection.Detection section 5 is exported to temporal frequency converter section 6 with the signal of institute's detection.

Detection section 5 carries out detection by orthogonal detection to digital signal.

(temporal frequency converter section)

Temporal frequency converter section 6 is the signal of frequency axis with the output of detection section 5 from the conversion of signals of time shaft.Adopt FFT as an example.Except FFT, can be the function of the signal of frequency axis from the conversion of signals of time shaft so long as have, get final product.For example, temporal frequency converter section 6 can be the parts that utilized fractal or other algorithms.

Temporal frequency converter section 6 is converted to the signal of frequency axis with the output of detection section 5 from time shaft, is extracted in data carrier, transmission control carrier wave and pilot frequency carrier wave that frequency axis is re-used thus.At this moment, if ofdm signal, thus then each carrier wave quadrature is re-used.

Temporal frequency converter section 6 is exported to balanced portion 7 and the 2nd lsb decoder 14 with data carrier of being extracted etc.

In addition, the temporal frequency conversion is carried out in the output that temporal frequency converter section 6 receives detection section 5, and it cuts the function of scope (window position) so preferably also have modulation.

By the schematically illustrated ofdm signal that is extracted by this temporal frequency converter section 6 of Fig. 2.

The transverse axis of Fig. 2 is a frequency axis, and the longitudinal axis is a time shaft.Each included carrier wave in each zero symbolic representation carrier group that Fig. 2 put down in writing.Each carrier wave is re-used on frequency axis, and on time shaft, these a plurality of carrier waves that are re-used are as 1 symbol, and this symbol is re-used on time shaft.

As shown in Figure 2, contain data carrier, pilot frequency carrier wave, the transmission control carrier wave of having modulated image or voice data.

(balanced portion)

Equilibrium portion 7 carries out the phase control of data carrier and transmission control carrier wave according to pilot frequency carrier wave.And the reliability value of expression accepting state is calculated by balanced portion 7.

Adopt Figure 10 that balanced portion 7 is described.Figure 10 is the internal module figure of the balanced portion in the embodiments of the present invention 2.

Equilibrium portion 7 possesses pilot tone generating unit 70, complex division portion 71, interpolating portion 72 and complex division portion 73.

Pilot frequency carrier wave is the known carrier wave of amplitude and phase place, in balanced portion 7, with the known pilot carrier wave pilot frequency carrier wave that is received is carried out multiple division, calculates the amplitude of the pilot frequency carrier wave that is received and the displacement of phase place thus.According to this displacement transmission path estimation state.

Pilot tone generating unit 70 produces the pilot frequency carrier wave with this known amplitude and phase place, and this known pilot carrier wave of complex division portion 71 usefulness carries out multiple division to the pilot frequency carrier wave that is received.

Thereby interpolating portion 72 will be calculated the only transmission path characteristic in the reception to the overlapping mean value of obtaining of result of the multiple division of a plurality of pilot frequency carrier waves.

Complex division portion 73 carries out multiple division according to the transmission path characteristic of being calculated to data carrier and transmission control carrier wave from 6 outputs of temporal frequency converter section, and these data carriers and transmission control carrier wave are carried out equilibrium.Equalization data carrier wave after the equilibrium and balanced transmission control carrier wave have been considered transmission path characteristic, so demodulation accuracy uprises.

Equilibrium portion 7 exports to error correction portion 8 with the equalization data carrier wave, and equilibrium transmission control carrier wave is exported to the 1st lsb decoder 9.

(error correction portion)

Error correction portion 8 corrects the mistake of numerical data included in institute's demodulated data carrier wave or the data carrier.

Error correction portion 8 carries out Viterbi (Viterbi) decoding or Reed-Solomon (Reed-Solomon) decoding etc., detects and correct the mistake of data carrier or data.By the numerical data after the error correction as exporting about the bag data of image or sound.

(the 1st lsb decoder, the 1st is corrected portion, the 1st synchronous detecting portion)

The 1st lsb decoder the 9, the 1st is corrected portion 10 as in execution mode 1 explanation like that, the equilibrium transmission is controlled carrier wave is decoded, error correction, exports the 1st control information.

The 1st synchronous detecting portion 11 exports the 1st synchronizing information thereby transmit the decoded result detection frame synchronization of controlling carrier wave from equilibrium as in execution mode 1 explanation.

(the 2nd lsb decoder, the 2nd is corrected portion, the 2nd synchronous detecting portion)

Transmission control carrier wave before 14 pairs of equilibriums of the 2nd lsb decoder is decoded.The function and the 1st lsb decoder 9 of decoding are equal, but realize by structure shown in Figure 11.

The 2nd lsb decoder 14 possesses differential lsb decoder 30, accumulation addition portion 31, polarity judging portion 32.

30 pairs of transmission control of differential lsb decoder carrier wave carries out differential decoding.By differential decoding, judge transmission control carrier wave is present in positive and negative which polarity on orthogonal plane.The result of 30 pairs of a plurality of transmission control carrier waves of 31 pairs of differential lsb decoders of accumulation addition portion accumulates.

Polarity judging portion 32 is according to the result who is accumulated, and the positive-negative polarity of carrier wave is controlled in the decision transmission.

In addition, transmission control carrier wave is present in the position of positive and negative any in the orthogonal plane (I, Q plane) in the ISDB-T specification.

The 2nd corrects portion 15 has structure and the function identical with correct portion 10 in the 1st of execution mode 1 explanation.Error correction is carried out in the 2nd output of correcting 15 pairs the 2nd lsb decoders 14 of portion, the 2nd control information after the output error correction.And the 2nd corrects portion 15 output comprises that the 2nd of " finishing " situation and " intact " situation separate code labeling, and " finishing " situation represents correctly to have carried out the error correction of the 2nd control information, and " intact " situation represents correctly not carry out the error correction of the 2nd control information.

The 2nd synchronous detecting portion 16 have with in the 1st synchronous detecting portion 11 of execution mode 1 explanation identical structure and function.Frame synchronization detects from the 2nd control information by 14 outputs of the 2nd lsb decoder in the 2nd synchronous detecting portion 16.The result who detects, the 2nd synchronizing information of the beginning position of the 2nd synchronous detecting portion 16 output expression frames.And the 16 output expressions of the 2nd synchronous detecting portion have detected the 2nd sync mark of synchronizing signal (having detected frame synchronization).The 2nd sync mark comprises " detecting " situation of representing successful frame synchronization and represents not " not detecting " situation of successful frame synchronization.

Here, the difference of the characteristic of the 1st lsb decoder 9 and the 2nd lsb decoder 14 is shown in the simulation result of Fig. 7, Fig. 9.

The 1st lsb decoder 9 antidamping noise circumstances are strong, and the 2nd lsb decoder 14 anti-white noise environments are strong.

(control information conciliation portion)

Control information conciliation portion 12 separates at least one that code labeling and the 2nd is separated code labeling according to the 1st, selects a side of the 1st control information and the 2nd control information.

Control information conciliation portion 12 corrects portion's 10 reception the 1st control informations and the 1st from the 1st and separates code labeling.And control information conciliation portion 12 corrects portion's 15 reception the 2nd control informations and the 2nd from the 2nd and separates code labeling.

Here as described above, the 1st separate code labeling and comprise that expression correctly carried out " intact " situation of the situation of " finishing " situation of situation of error correction of the 1st control information and the error correction that the 1st control information is not correctly carried out in expression.The 2nd separates code labeling comprises that expression correctly carried out " intact " situation of the situation of " finishing " situation of situation of error correction of the 2nd control information and the error correction that the 2nd control information is not correctly carried out in expression.

That is, the 1st each of separating that code labeling and the 2nd separates code labeling is the index of precision of the detection of the decoding of the corresponding transmission control carrier wave of expression and frame synchronization.

Control information conciliation portion 12 separates code labeling and the 2nd according to the 1st and separates code labeling, selects a side of the 1st control information and the 2nd control information.

Control information conciliation portion 12 exports to error correction portion 8 or the required key element of other signal demodulation with selected control information.

So, by the selection of control information conciliation portion 12, use the high control information of decode precision.

(synchronizing information conciliation portion)

A side of the 1st synchronizing information and the 2nd synchronizing information selects in synchronizing information conciliation portion 13.

Synchronizing information conciliation portion 13 receives the 1st synchronizing information from the 1st synchronous detecting portion 11, corrects portion's 10 receptions the 1st from the 1st and separates code labeling.And synchronizing information conciliation portion 13 receives the 2nd synchronizing information from the 2nd synchronous detecting portion 16, corrects portion's 15 receptions the 2nd from the 2nd and separates code labeling.

A side of the 1st synchronizing information and the 2nd synchronizing information selects according to the 1st sync mark and the 2nd sync mark in synchronizing information conciliation portion 13.

Synchronizing information conciliation portion 13 exports to error correction portion 8 or the required key element of other signal demodulation with selected control information.

So, by the selection of synchronizing information conciliation portion 13, use the high synchronizing information (frame synchronization) of accuracy of detection.

Here, by Fig. 7,9 simulation result as can be known, the 1st control information and the 1st synchronizing information antidamping noise circumstance are strong, the 2nd control information and the anti-white noise environment of the 2nd synchronizing information are strong.

Control information conciliation portion 12 can separate code labeling (these marks are by whether correctly having carried out the signal that error correction generates, so can think that it directly represents decode precision) and selects the high control information of decode precision according to separate code labeling and the 2nd as the 1st of the index of decode precision.Equally, synchronizing information conciliation portion 13 can be according to (these marks are the signals that generated by the detection of whether correctly having carried out frame synchronization as the 1st sync mark of the index of accuracy of detection and the 2nd sync mark, so can think that it directly represents accuracy of detection), select the high synchronizing information of accuracy of detection.

In addition, these are chosen in the process of time and are carried out (certainly, also can be undertaken by some cycles) at any time or one by one.That is to say, in the noise circumstance that at every moment changes, also carry out the selection of control information corresponding and synchronizing information neatly.As a result of, can realize to carry out the signal demodulating equipment 1 of the strong signal demodulation of antinoise environmental change.

(execution mode 3)

Below, execution mode 3 is described.

In execution mode 3, the various examples that the selection in control information conciliation portion 12 and the synchronizing information conciliation portion 13 is handled are described.

(example 1)

Control information conciliation portion 12 separates code labeling and the 2nd and separates under the situation of code labeling having obtained the 1st, selects in the 1st control information and the 2nd control information and the mark control information corresponding that comprises " finishing " situation.

For example, separating code labeling the 1st is that " finishing " situation, the 2nd is separated under the situation that code labeling is " intact " situation, and control information conciliation portion 12 selects conduct and the 1st to separate the 1st control information of code labeling control information corresponding.On the contrary, separating code labeling the 1st is that " intact " situation, the 2nd is separated under the situation that code labeling is " a finishing " situation, and control information conciliation portion 12 selects conduct and the 2nd to separate the 2nd control information of code labeling control information corresponding.

Synchronizing information conciliation portion 13 is selected and the corresponding synchronizing information of mark that comprises " detecting " situation in the 1st synchronizing information and the 2nd synchronizing information under the situation that has obtained the 1st sync mark and the 2nd sync mark.

For example, be that " detecting " situation, the 2nd sync mark are under the situation of " not detecting " situation in the 1st sync mark, the 1st synchronizing information that synchronizing information conciliation portion 13 is selected as the synchronizing information corresponding with the 1st sync mark.On the contrary, be that " not detecting " situation, the 2nd sync mark are under the situation of " detecting " situation in the 1st sync mark, the 2nd synchronizing information that synchronizing information conciliation portion 12 is selected as the synchronizing information corresponding with the 2nd sync mark.

So, by separating the situation that code labeling and the 2nd is separated code labeling " finishing " " intact " according to the 1st, signal demodulating equipment 1 can be easily and is used the high control information of decode precision reliably.Equally, by the situation that " detecting " according to the 1st sync mark and the 2nd sync mark " do not detect ", signal demodulating equipment 1 can be easily and is used the high detection information of accuracy of detection reliably.

(example 2)

The following describes example 2.

Obtaining the 1st separates code labeling and the 2nd and separates code labeling, in the situation of any mark all is under the situation of same levels (two marks all represent situation of " finishing " or two marks all represent the situation of " intact "), and the control information just selected is selected by control information conciliation portion 12 in the 1st control information and the 2nd control information.

For example, all be that the selection before being right after has been selected under the situation of the 1st control information in handling under the situation of " intact " situation in the 1st any of separating that code labeling and the 2nd separates code labeling, the 1st control information is selected by control information conciliation portion 12.Perhaps, all be under the situation of " finishing " situation in the 1st any of separating that code labeling and the 2nd separates code labeling, the selection before being right after has been selected under the situation of the 2nd control information in handling, and the 2nd control information is selected by control information conciliation portion 12.

Obtain the 1st sync mark and the 2nd sync mark, situation at any mark all is under the same levels situation of (two marks are all represented situation of " detecting " or the situation that two marks are all represented " not detecting "), and the synchronizing information just selected is selected by synchronizing information conciliation portion 13 in the 1st synchronizing information and the 2nd synchronizing information.

For example, all be under the situation of " not detecting " situation in any of the 1st sync mark and the 2nd sync mark, the selection before being right after has been selected under the situation of the 1st synchronizing information in handling, and the 1st synchronizing information is selected by synchronizing information conciliation portion 13.Perhaps, all be under the situation of " detecting " situation in any of the 1st sync mark and the 2nd sync mark, the selection before being right after has been selected under the situation of the 2nd synchronizing information in handling, and the 2nd synchronizing information is selected by synchronizing information conciliation portion 13.

So, by control information or the synchronizing information of selecting just to have selected, can select only control information or synchronizing information.

(example 3)

The following describes example 3.

Control information conciliation portion 12 measures in specified time limit the 1st and separates the number that code labeling and the 2nd is separated the mark of expression " finishing " situation in the code labeling.The result of metering, control information conciliation portion 12 is selected and the mark control information corresponding of Duoing than the number of " finishing ".

For example, in specified time limit, the 1st number of separating code labeling of expression " finishing " situation is that 10, the 2nd number of separating code labeling of expression " finishing " situation are under 14 the situation, and control information conciliation portion 12 selects to separate the 2nd corresponding control information of code labeling with the 2nd.On the contrary, be that 20, the 2nd number of separating code labeling of expression " finishing " situation are under 10 the situation in the 1st number of separating code labeling of expression " finishing " situation, control information conciliation portion 12 selects to separate the 1st corresponding control information of code labeling with the 1st.

Synchronizing information conciliation portion 13 measures the number of the mark of expression " detecting " situation in the 1st sync mark and the 2nd sync mark in specified time limit.The result of metering, the synchronizing information corresponding with the mark of Duoing than the number of " detecting " selected by synchronizing information conciliation portion 13.

For example, in specified time limit, in the number of the 1st sync mark of expression " detecting " situation is that 10, the number of the 2nd sync mark of expression " detecting " situation are that 2nd synchronizing information corresponding with the 2nd sync mark selected by synchronizing information conciliation portion 13 under 14 the situation.On the contrary, be that 20, the number of the 2nd sync mark of expression " detecting " situation are that 1st synchronizing information corresponding with the 1st sync mark selected by synchronizing information conciliation portion 13 under 10 the situation in the number of the 1st sync mark of expression " detecting " situation.

So, by selection and the mark control information corresponding or the synchronizing information that comprise that in specified time limit " finishing " or " detecting " situation is many, thereby can realize the signal demodulation that precision is higher.

In addition, the selection that also can make up each example 1～example 3 is handled.

(other)

In addition, adopt Figure 12 to illustrate that the 1st separates the raising of calculating precision that code labeling, the 2nd is separated code labeling, the 1st sync mark and the 2nd sync mark.

Under the 1st control information that present frame is decoded and the situation consistent to the 1st control information that forward frame is decoded than present frame in time, the 1st decoding mark is represented " finishing " situation, the 1st control information that present frame is decoded with to the inconsistent situation of the 1st control information that forward frame is decoded than present frame in time under, the 1st decoding mark is represented " intact " situation.

Control information conciliation portion 12 can carry out the selection of control information according to based on the code labeling of separating to the comparison of the control information of the frame that is separated on such time.Perhaps, also consistent, inconsistent information can be added the 1st and separated code labeling, on the basis that the 1st precision of separating code labeling is improved, control information conciliation portion 12 uses the 1st to separate code labeling thus.

As shown in figure 12, at first, the output signal of the 1st lsb decoder 9 is imported the 1st and is corrected portion 10 and frame delay portion 35.Frame delay portion 35 makes the 1st control information postpone 1 frame.Comparing section 36 relatively directly input the 1st control information (to the 1st control information of present frame) and postponed the 1st control information (to the 1st control information of frame more forward on the time) of 1 frame than present frame.Under the situation of two the 1st control information unanimities, the consistent mark of comparing section 36 output expression, under two the 1st inconsistent situations of control information, the inconsistent mark of output expression.The mark of expression unanimity represents that corresponding to the 1st " finishing " situation of separating code labeling inconsistent mark is corresponding to the 1st " intact " situation of separating code labeling.

The 1st corrects portion 10 carries out error correction at the 1st control information to present frame, and the 1st of the state of output expression error correction is separated code labeling.The 1st separates code labeling exports to mark selection portion 37.

Mark selection portion 37 is selected to correct the 1st of portion's 10 outputs from the 1st and is separated code labeling, exports to control information conciliation portion 12.At this moment, control information conciliation portion 12 separates code labeling and the 2nd according to the 1st and separates code labeling as in execution mode 1～3 explanation, selects a side of the 1st control information and the 2nd control information.

Perhaps, also can mark selection portion 37 will separate the equal mark of code labeling with the 1st, export to control information conciliation portion 12 from mark (expression is consistent, the inconsistent) conduct of comparing section 36 outputs.At this moment, consistent the 1st " finishing " situation of separating code labeling that is equivalent to, inconsistent the 1st " not intact " situation of separating code labeling that is equivalent to.That is, control information conciliation portion 12 can with should unanimity, inconsistent mark is as the selection reference of the 1st control information and the 2nd control information.In other words, when the 1st control information that the 1st control information of decoding at present frame and more forward than present frame in time frame are decoded was inconsistent, control information conciliation portion 12 can be judged as the reliability of the 1st control information of being decoded low.Be judged as under the low situation of reliability, the 1st control information can not selected by control information conciliation portion 12, then selects the 2nd control information.

Equally, the 2nd separate code labeling also can be by come the expression situation the decoded result of present frame and the 2nd control information of more forward than present frame in time frame consistent, inconsistent.

The 1st sync mark, the 2nd sync mark are too.

In addition, correct the 1st of portion's 10 outputs from the 1st and separate code labeling, can add the situation that the 1st of past frame is separated code labeling, can carry out the higher selection of precision and handle at the 1st of present frame being separated code labeling by using to shelter from the mark of comparing section 36 output.

(execution mode 4)

The following describes execution mode 4.

Each function of illustrated signal demodulating equipment can realize with hardware in execution mode 1～3, also can realize with software.In addition, can also realize by loading in mixture of hardware and software.

Thereby receiving definite frequency band with the transmitting signal that antenna 2 receives in tuner 3 is received as received signal.

Processor 58 is realized each included function of signal demodulating equipment by calculation process.At this moment, processor 58 is carried out the signal demodulation according to institute's program stored among the ROM59.

In addition, processor 58 is CPU or DSP here.In addition, in Figure 13, antenna 2 and tuner 3 only are shown, but tuner 3 can be realized also with software as hardware elements.

Processor 58 reads in program stored among the ROM59, carries out the computing according to the processing sequence of program, carries out the signal demodulation.Adopt Figure 14 that the flow process of the signal demodulation that processor 58 carries out is described.Figure 14 is the flow chart of the signal demodulating method in the embodiments of the present invention 4.

At first in step ST1, processor 58 is converted to digital signal with the received signal of analog signal.Then, in step ST2, the digital signal after 58 pairs of conversions of processor is carried out detection.Orthogonal detection is adopted in detection.

Then, in step ST3, processor 58 is the signal of frequency axis with the digital signal after the detection from the conversion of signals of time shaft.The output of step ST3 conveys to step ST4 and step ST9.By being converted to the signal of frequency axis, control carrier wave thereby be extracted in the data carrier, pilot frequency carrier wave and the transmission that are re-used on the frequency axis.

In step ST9, the transmission control carrier wave that is extracted thereby decoding is converted to the signal of frequency axis obtains the 2nd control information.In step ST10, carry out the error correction of the 2nd control information, the 2nd of the situation of the 2nd control information after the output error correction and expression error correction is separated code labeling.Equally, in step ST11, thereby processor 58 detects the 2nd sync mark that frame synchronization is exported the state of the 2nd synchronizing information and the detection of expression frame synchronization according to the 2nd control information.

In step ST4, the ofdm signal that 58 pairs of processors are converted to frequency axis carries out equilibrium.Processor 58 is exported to next step ST5 by equilibrium with equilibrium transmission control carrier wave.Step ST5～ST7 and above-mentioned steps ST9～ST11 And carry out capablely.

In step ST5, thereby the balanced transmission control of processor 58 decodings carrier wave is exported the 1st control information.Then, in step ST6, error correction is carried out in 58 pairs the 1st control informations of processor, and the 1st of the situation of the 1st control information after the output error correction and expression error correction is separated code labeling.And in step ST7, thereby processor 58 detects the 1st sync mark that frame synchronization is exported the state of the 1st synchronizing information and the detection of expression frame synchronization according to the 1st control information.

Use the 1st is separated code labeling, the 2nd and is separated code labeling, the 1st control information and the 2nd control information in step ST8.In step ST8, processor 58 is separated code labeling and the 2nd according to the 1st and is separated code labeling, selects a side of the 1st control information and the 2nd control information.

In step ST12, use the 1st sync mark, the 2nd sync mark, the 1st synchronizing information and the 2nd synchronizing information.In step ST12, processor 58 is selected a side of the 1st synchronizing information and the 2nd synchronizing information according to the 1st sync mark and the 2nd sync mark.

Here, the selection among step ST8 and the step ST12 is handled with same in the illustrated processing of execution mode 3.

By above such signal demodulating method, in white noise environment, select the 2nd control information and the 2nd synchronizing information become easily (the 2nd control information and the anti-white noise environment of the 2nd synchronizing information are strong), in the attenuate acoustic noise environment, select the 1st control information and the 1st synchronizing information become easily (the 1st control information and the 1st synchronizing information antidamping noise circumstance are strong).

This result can realize the decoding of only control information and the detection of frame synchronization at the noise circumstance that at every moment changes.

In addition, the part of each key element of step shown in Figure 14 is except based on realizing with hardware the software of program.The processing of each key element is same with function, processing in execution mode 1～3 explanation in addition.

(execution mode 5)

Adopt Figure 15 that execution mode 5 is described below.

Execution mode 5 explanation realizes all or part of situation of signal demodulating equipment with semiconductor integrated circuit.Figure 15 is the module map of the semiconductor integrated circuit in the embodiments of the present invention 5.

Semiconductor integrated circuit 80 possesses in the illustrated key element of execution mode 1～3.That is, semiconductor integrated circuit 80 contains tuner function, analog digital translation function, detection function, temporal frequency translation function, equalization function, error correction, the 1st decoding function, the 1st and corrects function, the 1st synchronous detecting function, the 2nd decoding function, the 2nd and correct function, the 2nd synchronous detecting function, control information mediation function and synchronizing information mediation function.Each function is with same in the function of execution mode 1～3 explanation.

80 pairs of semiconductor integrated circuit are changed by temporal frequency and the transmission control carrier wave that extracts is decoded, and obtain the 2nd control information and the 2nd synchronizing information.In addition, the equilibrium transmission control carrier wave after 80 pairs of equilibriums of semiconductor integrated circuit is decoded, and obtains the 1st control information and the 1st synchronizing information.Semiconductor integrated circuit selects to use a side of the 1st control information and the 2nd control information according to the index (the 1st separates code labeling and the 2nd separates code labeling) of expression decode precision.Equally, semiconductor integrated circuit selects to use a side of the 1st synchronizing information and the 2nd synchronizing information according to the index (the 1st sync mark and the 2nd sync mark) of expression accuracy of detection.The 1st control information and the 1st synchronizing information antidamping noise circumstance are strong.The 2nd control information and the anti-white noise environment of the 2nd synchronizing information are strong.

Its result, semiconductor integrated circuit 80 can be realized the only signal demodulation of noise circumstance of variation at every moment.

In addition, the selection of control information or synchronizing information is handled with same in the processing of execution mode 3 explanations.In addition, also can be by the part of the software processes function in the processor 83.

In addition, as shown in figure 15, thereby semiconductor integrated circuit 80 also can be connected the utilization of carrying out necessary control or demodulation result with ROM81, RAM82, processor 83.

(execution mode 6)

Adopt Figure 16 that execution mode 6 is described below.

Execution mode 6 explanation possesses the receiving system at the illustrated signal demodulating equipment 1 of execution mode 1～3.

Key element with symbol identical with Fig. 4 is with same at the illustrated parts of execution mode 1～3.

Receiving system 90 among Figure 16 has increased lsb decoder 91 in the signal receiving device 1 with Fig. 4 explanation.

91 pairs of data carriers by 8 outputs of error correction portion of lsb decoder are decoded, and take out included image or acoustic information in the data carrier, become the state that in fact can show.Though in Figure 16, do not illustrate, can also possess display unit or loud speaker etc., carry out image and show or sound reproduction.

Also has the function of the signal demodulating equipment that illustrates at execution mode 1～3 at the receiving system 90 of execution mode 6 explanations, so the most suitably corresponding signal demodulation of noise circumstance that can carry out and at every moment change.As a result of, can carry out the reception of the strong ofdm signal of antinoise environmental change.

In addition, receiving system also is suitable for being installed in the electronic equipments such as portable phone, portable terminal device, PDA, auto navigation, in-car TV, car-mounted terminal.Because thereby these equipment receive the regeneration that ofdm signal carries out television broadcasting or broadcast receiver broadcasting.

For example, as shown in figure 17, can be installed in the portable phone.Figure 17 is the stereogram of the portable phone in the embodiments of the present invention 6.Portable phone 95 possesses display part 96.And portable phone 95 possesses the receiving system in Figure 16 explanation.

Portable phone 95 receives the signal that comprises ofdm signal.And, the signal demodulation that portable phone 95 is carried out in execution mode 1～3 explanation.Finally, portable phone 95 shows the image of being regenerated at display part 96, or from loud speaker regeneration sound.

In this case, also carry out signal demodulation, so can carry out the signal reception most suitably corresponding with the variation of noise circumstance in execution mode 1～4 explanation.

In addition, portable phone 95 is examples that the electronic equipment of receiving system has been installed, except the TV or AV equipment, timer etc. of arrangement type, can also be applied to portable terminal (portable terminal device, portable phone, in-car TV, auto-navigation system, pocket TV, pocket broadcast receiver, laptop).

In addition, signal demodulating equipment of the present invention, signal demodulating method, semiconductor integrated circuit and receiving system not only are suitable for also being suitable for the demodulation corresponding to frequency-division multiplex singal corresponding to the ofdm signal of following the ISDB-T specification.

Here, the transmission in ISDB-T specification control carrier wave FFT hits information, protection at least one of (guard interval) long letter breath and symbol long letter breath etc. at interval of comprising with the ofdm signal frequency-division multiplex singal that is representative.In the specification beyond the ISDB-T specification, transmission control carrier wave comprises at least one of modulation demodulation system information, communication mode information and transmission means information of frequency-division multiplex singal (signal that is transmitted).In about the transmission of the signal in the specification of face of land ground roll broadcasting, transmission signals contains various control informations or pattern information, and signal demodulating equipment is resolved this control information or pattern information, can receive thus and demodulation.Here, pattern information contains at least one of modulation demodulation system information, communication mode information and transmission means information.

In addition, modulation demodulation system information comprises for example mode of QPSK, BPSK, 16QAM, 64QAM etc.Communication mode information or transmission means information comprise for example value of transmission frequency or transmission band etc.

So, signal demodulating equipment, signal demodulating method, semiconductor integrated circuit and receiving system can utilize at least one of modulation demodulation system information, communication mode information and transmission means information, come demodulated received signal corresponding to the transmission signals of all size.

In addition, the signal demodulating equipment, signal demodulating method, semiconductor integrated circuit and the receiving system that illustrate at execution mode 1～6 are examples of purport explanation of the present invention, are included in the distortion or the transformation of the scope that does not break away from purport of the present invention.

Utilizability on the industry

The present invention can suit to utilize such as the portable terminal device that receives terrestrial digital broadcasting or the field of the employed signal demodulating equipment of portable terminal or receiving system etc.

Claims

1. signal demodulating equipment is characterized in that possessing:

The temporal frequency converter section, it is converted to signal on the frequency axis with the frequency-division multiplex singal on the time shaft, dateout carrier wave, pilot frequency carrier wave and transmission control carrier wave;

Equilibrium portion, it carries out equilibrium according to from the transmission path characteristic value that described pilot frequency carrier wave obtained to described data carrier and described transmission control carrier wave, thus output equalization data carrier wave and balanced transmission control carrier wave;

The 1st lsb decoder, it is decoded to described balanced transmission control carrier wave; With

The 1st corrects portion, and error correction is carried out in its output to described the 1st lsb decoder, thus export the 1st control information and expression error correction state the 1st separate code labeling.

2. signal demodulating equipment according to claim 1 is characterized in that also possessing:

The 2nd lsb decoder, it is decoded to the described transmission control carrier wave from described temporal frequency converter section output;

The 2nd corrects portion, and error correction is carried out in its output to described the 2nd lsb decoder, thus export the 2nd control information and expression error correction state the 2nd separate code labeling; With

Control information conciliation portion, it separates code labeling and described the 2nd at least one of separating in the code labeling according to the described the 1st, selects in described the 1st control information and described the 2nd control information any.

3. signal demodulating equipment according to claim 2 is characterized in that also possessing:

The 1st synchronous detecting portion, its output according to described the 1st lsb decoder detects frame synchronization, and exports the 1st sync mark of the state of the 1st synchronizing information and the detection of expression frame synchronization;

The 2nd synchronous detecting portion, its output according to described the 2nd lsb decoder detects frame synchronization, and exports the 2nd sync mark of the state of the 2nd synchronizing information and the detection of expression frame synchronization; With

Synchronizing information conciliation portion, it selects any in described the 1st synchronizing information and described the 2nd synchronizing information according in described the 1st sync mark and described the 2nd sync mark at least one.

4. signal demodulating equipment according to claim 3 is characterized in that,

The described the 1st separates the situation that code labeling comprises " intact " when " finishing " when the error correction of the 1st control information has correctly been carried out in expression and expression are not correctly carried out error correction,

The described the 2nd separates the situation that code labeling comprises " intact " when " finishing " when the error correction of the 2nd control information has correctly been carried out in expression and expression are not correctly carried out error correction,

Described the 1st sync mark and described the 2nd sync mark comprise " detecting " and the situation of expression " not detecting " can not detect frame synchronization time the when expression can detect frame synchronization respectively.

5. signal demodulating equipment according to claim 4 is characterized in that,

Described control information conciliation portion is selected in described the 1st control information and described the 2nd control information and the described situation control information corresponding of finishing,

Described synchronizing information conciliation portion is selected and the corresponding synchronizing information of described detected situation in described the 1st synchronizing information and described the 2nd synchronizing information.

6. signal demodulating equipment according to claim 4 is characterized in that,

The control information just selected is selected by described control information conciliation portion in described the 1st control information and described the 2nd control information when the described the 1st separates code labeling and described the 2nd decoding mark and represent the situation of same levels,

The synchronizing information of just having selected is selected by described synchronizing information conciliation portion in described the 1st synchronizing information and described the 2nd synchronizing information when the situation of same levels is represented in described the 1st sync mark and described the 2nd sync mark.

7. signal demodulating equipment according to claim 4 is characterized in that,

Described control information conciliation portion is in specified time limit, separating code labeling and the described the 2nd the described the 1st separates in the code labeling, the number of the described situation of finishing of metering expression, described control information conciliation portion is in described the 1st control information and described the 2nd control information, selection with Duo than described number separate the code labeling control information corresponding

Described synchronizing information conciliation portion is in specified time limit, in described the 1st sync mark and described the 2nd sync mark, the number of the described detected situation of metering expression, the synchronizing information corresponding with the sync mark of Duoing than described number selected by described synchronizing information conciliation portion in described the 1st synchronizing information and described the 2nd synchronizing information.

8. signal demodulating equipment according to claim 4 is characterized in that,

To the 1st control information of present frame with to the time on the 1st control information of the frame more forward when consistent than present frame, described the 1st decoding mark is represented the described situation of finishing, when the 1st control information of the frame more forward than present frame is inconsistent to the 1st control information of present frame with on to the time, described the 1st decoding mark is represented described not intact situation

To the 2nd control information of present frame with to the time on the 2nd control information of the frame more forward when consistent than present frame, described the 2nd decoding mark is represented the described situation of finishing, when the 2nd control information of the frame more forward than present frame was inconsistent to the 2nd control information of present frame with on to the time, described the 2nd decoding mark was represented described not intact situation.

9. signal demodulating equipment according to claim 1 is characterized in that also possessing:

Tuner, its reception comprise the signal that belongs to definite frequency band that the received signal of described frequency-division multiplex singal is interior, and the output analog signal;

The analog digital converter section, it is a digital signal with described analog signal conversion;

Detection section, it carries out detection to described digital signal, and the signal that institute's detection obtains is exported to described temporal frequency converter section; With

Error correction portion, it carries out the error correction of described equalization data carrier wave.

10. a signal demodulating method is characterized in that, comprises the steps:

The temporal frequency switch process is converted to signal on the frequency axis with the frequency-division multiplex singal on the time shaft, dateout carrier wave, pilot frequency carrier wave and transmission control carrier wave;

Equalization step according to from the transmission path characteristic value that described pilot frequency carrier wave obtained, is carried out equilibrium to described data carrier and described transmission control carrier wave, output equalization data carrier wave and balanced transmission control carrier wave;

The 1st decoding step is decoded to described balanced transmission control carrier wave; With

The 1st corrects step, and error correction is carried out in the output of described the 1st lsb decoder, thus export the 1st control information and expression error correction state the 1st separate code labeling.

11. signal demodulating method according to claim 10 is characterized in that, also comprises:

The 2nd decoding step is decoded to the described transmission control carrier wave of being exported in described temporal frequency switch process;

The 2nd corrects step, and error correction is carried out in the output of described the 2nd decoding step, export the 2nd control information and expression error correction state the 2nd separate code labeling; With

Step is reconciled in control information, separates code labeling and described the 2nd at least one of separating in the code labeling according to the described the 1st, selects in described the 1st control information and described the 2nd control information any.

12. signal demodulating method according to claim 11 is characterized in that, comprising:

The 1st synchronous detecting step detects frame synchronization according to the output of described the 1st decoding step, exports the 1st sync mark of the state that the 1st synchronizing information and expression frame synchronization detects;

The 2nd synchronous detecting step detects frame synchronization according to the output of described the 2nd decoding step, exports the 2nd sync mark of the state that the 2nd synchronizing information and expression frame synchronization detects; With

Synchronizing information is reconciled step, according in described the 1st synchronizing information and described the 2nd synchronizing information at least one, selects any in described the 1st synchronizing information and described the 2nd synchronizing information.

13. signal demodulating method according to claim 12 is characterized in that,

14. a semiconductor integrated circuit is characterized in that possessing:

The 1st lsb decoder, it is decoded to described balanced transmission control carrier wave;

The 1st corrects portion, and error correction is carried out in its output to described the 1st lsb decoder, export the 1st control information and expression error correction state the 1st separate code labeling;

The 2nd corrects portion, and error correction is carried out in its output to described the 2nd lsb decoder, export the 2nd control information and expression error correction state the 2nd separate code labeling; With

15. semiconductor integrated circuit according to claim 14 is characterized in that, possesses:

The 1st synchronous detecting portion, its output according to described the 1st lsb decoder detects frame synchronization, exports the 1st sync mark of the state of the 1st synchronizing information and the detection of expression frame synchronization;

The 2nd synchronous detecting portion, its output according to described the 2nd lsb decoder detects frame synchronization, exports the 2nd sync mark of the state of the 2nd synchronizing information and the detection of expression frame synchronization; With

16. semiconductor integrated circuit according to claim 15 is characterized in that,

17. a receiving system is characterized in that possessing:

Antenna, its reception comprises the signal of frequency-division multiplex singal;

Tuner, its reception belongs to the signal of definite frequency band of the received signal that is received by described antenna, and the output analog signal;

Detection section, it carries out detection to described digital signal, and rectified signal is exported to described temporal frequency converter section;

The temporal frequency converter section, it is the signal of frequency axis with described rectified signal from the conversion of signals of time shaft, and dateout carrier wave, pilot frequency carrier wave and transmission control carrier wave;

Equilibrium portion, it carries out equilibrium according to from the transmission path characteristic value that described pilot frequency carrier wave obtained to described data carrier and described transmission control carrier wave, output equalization data carrier wave and balanced transmission control carrier wave;

The 2nd corrects portion, and error correction is carried out in its output to described the 2nd lsb decoder, export the 2nd control information and expression error correction state the 2nd separate code labeling;

Control information conciliation portion, it separates code labeling and described the 2nd at least one of separating in the code labeling according to the described the 1st, selects in described the 1st control information and described the 2nd control information any;

The 2nd synchronous detecting portion, its output according to described the 2nd lsb decoder detects frame synchronization, exports the 2nd sync mark of the state of the 2nd synchronizing information and the detection of expression frame synchronization;

Synchronizing information conciliation portion, it selects any in described the 1st synchronizing information and described the 2nd synchronizing information according in described the 1st sync mark and described the 2nd sync mark at least one;

Error correction portion, it carries out the error correction of described equalization data carrier wave; With

Data decoding part, the described equalization data carrier wave that it adopts after the error correction comes decoded data.

18. signal demodulating equipment according to claim 1 is characterized in that,

Described frequency-division multiplex singal is the orthogonal frequency-division multiplex singal that a plurality of carrier waves of being re-used on frequency axis are re-used in mutually orthogonal mode.

19. signal demodulating equipment according to claim 18 is characterized in that,

Described orthogonal frequency-division multiplex singal is a defined signal in 1 section broadcasting in the ground surface wave number word broadcasting.